Abstract Factory pattern -- Structural example

UML class diagram

![](http://www.dofactory.com/Patterns/Diagrams/abstract.gif)  

using System;


// "AbstractFactory"


abstract class AbstractFactory  
{  
  // Methods  
  abstract public AbstractProductA CreateProductA();  
  abstract public AbstractProductB CreateProductB();  
}


// "ConcreteFactory1"


class ConcreteFactory1 : AbstractFactory  
{  
  // Methods  
  override public AbstractProductA CreateProductA()  
  {  
    return new ProductA1();  
  }  
  override public AbstractProductB CreateProductB()  
  {  
    return new ProductB1();  
  }  
}


// "ConcreteFactory2"


class ConcreteFactory2 : AbstractFactory  
{  
  // Methods  
  override public AbstractProductA CreateProductA()  
  {  
    return new ProductA2();  
  }  
  override public AbstractProductB CreateProductB()  
  {  
    return new ProductB2();  
  }  
}


// "AbstractProductA"


abstract class AbstractProductA  
{  
}


// "AbstractProductB"


abstract class AbstractProductB  
{  
  // Methods  
  abstract public void Interact( AbstractProductA a );  
}


// "ProductA1"


  
class ProductA1 : AbstractProductA  
{  
}


// "ProductB1"


class ProductB1 : AbstractProductB  
{  
  // Methods  
  override public void Interact( AbstractProductA a )  
  {  
    Console.WriteLine( this + " interacts with " + a );  
  }  
}


// "ProductA2"


class ProductA2 : AbstractProductA  
{  
}


// "ProductB2"


class ProductB2 : AbstractProductB  
{  
  // Methods  
  override public void Interact( AbstractProductA a )  
  {  
    Console.WriteLine( this + " interacts with " + a );  
  }  
}


// "Client" - the interaction environment of the products


class Environment  
{  
  // Fields  
  private AbstractProductA AbstractProductA;  
  private AbstractProductB AbstractProductB;


  // Constructors  
  public Environment( AbstractFactory factory )  
  {  
    AbstractProductB = factory.CreateProductB();  
    AbstractProductA = factory.CreateProductA();  
  }  
    
  // Methods  
  public void Run()  
  {  
    AbstractProductB.Interact( AbstractProductA );  
  }  
}


///

1<summary>  
2    ///  ClientApp test environment  
3    /// </summary>

class ClientApp
{
  public static void Main(string[] args)
  {
    AbstractFactory factory1 = new ConcreteFactory1();
    Environment e1 = new Environment( factory1 );
    e1.Run();

    AbstractFactory factory2 = new ConcreteFactory2();  
    Environment e2 = new Environment( factory2 );  
    e2.Run();


    Console.Read();  
  }  
}